Left-hander Jesús Luzardo, the A’s top pitching prospect, has not yet resumed throwing after being shut down March 21 because of a sore left shoulder, but there was encouraging news Sunday.

“Luzardo feels absolutely fantastic,” Oakland manager Bob Melvin said. “He’s chomping at the bit. He wants to throw. But we understand for a guy like him, when you set a timetable, there’s really no need to speed it up. We just want to make sure when he comes back, he’s fully healthy.

“Are we excited about getting him back at some point? Absolutely.”

Shoulder injuries are of particular concern because shoulder surgery does not have the success rate of elbow-ligament replacement (Tommy John)operations. And shutting down any pitcher for a month or more with any type of injury usually indicates some significant concern. The A’s shut down Luzardo for four to six weeks.

Even should Luzardo start throwing again in the next few weeks, he would be unlikely to pitch in minor-league games for an additional month to six weeks after that because he essentially needs to go through spring training again. On that type of schedule, he realistically would not be available to pitch in the big leagues until June, and that’s if all goes perfectly.